Background: This study has investigated the association between
haptoglobin (Hp) polymorphism and the occurrence of chronic renal failure (CRF) in
Jordanians.
Methods: Blood specimens were collected from 159 patients with CRF
resulting from various predisposing conditions and from 200 healthy unrelated
controls. Hp phenotyping was conducted using polyacrylamide gel electrophoresis.
Results: The Hp 2-2 phenotype was over-represented in CRF patients in
general (0.547), patients with hypertension (0.622) and patients with diabetes
mellitus (0.633). The Hp 2-1 phenotype was over-represented in patients with chronic
glomerulonephritis (0.549) and patients with reflux nephropathy (0.445). In patients
with polycystic kidney disease (PKD), only Hp 2-1 and Hp 2-2 were detected, occurring
at a frequency of 0.214 and 0.786, respectively. The frequency of Hp 2 allele in PKD
patients was 0.893 compared with 0.706 in the control group. Hp-type distribution was
in agreement with the expectations of a population in Hardy-Weinberg equilibrium in
all groups except for the hypertensive patients.
Conclusions: Haptoglobin homozygosity seems to represent a possible risk
factor for CRF in hypertensive, diabetic and PKD patients; Hp heterozygosity may lead
to chronic glomerulonephritis.
